1. Field of the Invention
The present invention relates generally to dump truck trailers and more specifically to a dump trailer which is capable of storing and dumping two separate loads of goods.
2. Description of the Related Art
Semi trucks with dump trailers are commonly utilized to move or haul large quantities of dirt, gravel, grains, or the like and then to dump it into stockpiles or to spread it over an area. Semi trailers are designed to split the load weight between the fifth wheel and the rear axle. In order to comply with bridge load laws, the wheel axles are spaced apart a minimum distance of approximately 32 feet. The cargo box generally extends from the fifth wheel to the end of the trailer over the rear axle.
However, if the box is used as a dump box, there is a tendency for the trailer to tip when the box is elevated because of the extreme height a long box reaches during the dumping process. This can be caused by uneven loading of the box, uneven or soft ground conditions, or if the box is exposed to high wind conditions. The risk of tipping creates a considerable financial liability to the owner and/or operator and a serious safety hazard to the operator and spectators around the truck while dumping. To minimize this effect, existing dump trailers have been reduced in length with a corresponding decrease in payload. Currently only a single load of goods may be carried at one time. Therefore, the vehicle must make multiple trips to haul all of the goods needed. As a result many improvements in the method of an apparatus for hauling and dumping material have been developed.
For example, in U.S. Pat. No. 5,344,271, issued in the name of Bratlie et al., a trailer dumper is disclosed having a low profile tipper with a little deck which can be utilized for successfully removing the contents from a plurality of trailers.
Also, in U.S. Pat. No. 4,877,293, issued in the name French et al., a load bridging dump trailer is disclosed having a cargo box pivotally mounted on the rear end of a trailer frame thereby allowing the cargo box to be pivoted thereon.
And, in U.S. Pat. No. 4,659,147, issued in the name of Smiltneek, a dump trailer is disclosed having a towable, dumpable trailer capable of dumping without the need for hydraulic or electrical devices.
Again, in U.S. Pat. No. 3,771,829, issued in the name Breazeale et al., a dump trailer is disclosed utilizing an extended drive shaft in order to remotely drive a hitched dump trailer portion.
Finally, U.S. Pat. No. 3,193,330, issued in the name Hriear Jr., a dump trailer is disclosed similar to that in the Breazeale et al, reference but utilizing a hydraulic take off rather than a mechanical drive shaft.
In spite of all these improvements, a need is still felt for an apparatus which can increase the payload of a dumping trailer, minimize the required dumping height, reduce financial risk, improve safety, and cut insurance costs, as well as provide a separable method of carrying more than one payload.